Use of double shock compression to eliminate Richtmyer–Meshkov instability growth*

We employ a carefully designed composite PMMA/Ta impactor to completely eliminate Richtmyer-Meshkov instability (RMI) jet growth from a V-groove in a PMMA target. In an identical control target with a Ta impactor, upon breakout a significant RMI jet is launched from the V-groove, illustrating the effectiveness of this mitigation method. We observe RMI jet growth using time-resolved x-ray imaging of gas gun experiments at the Dynamic Compression Sector. In these experiments, the surface is imaged up to ~1 μs after breakout, sufficient to establish steady state surface motion without jet growth. Since this method employs only modulation of the compression drive profile, it does not require special target design and may be used for laser driven compression as well. We find good agreement between the experimental data and simulations.